The Dispersed Fourier Transform Spectrometer (DFTS) is a further modernization of the 1883 invention by Dr. Albert Michelson, who laid the theoretical basis for the Fourier Transform Spectrometer (FTS). The DFTS, as outlined in U.S. Pat. No. 7,206,073, which is hereby incorporated by reference in its entirety, consists of an FTS with a grating spectrometer and a metrology sub-system that can discern sub-nanometer vibrations and displacements, as well as discriminate and identify molecular species.
The DFTS was designed to investigate and characterize extra-solar stellar masses and motions at cosmic distances; it possesses the requisite high level of sensitivity to accomplish such tasks. However, the DFTS has not been applied to the problem of remotely sensing targets within the terrestrial domain. It is desirable to provide both systems and methods of implementing such systems, which capitalize on the capability of the DFTS to both: (1) detect differential motions and vibrations by measuring the variation in fringe shifts present with different spectral bands, and (2) differentiate between molecular species by using combinations of different spectral bands.